UPDATE: TOLLS are being waived for both directions of the Logan Motorway at Loganlea as traffic builds on the M1, after a tanker carrying 15,000 litres of hydrochloric acid burst into flames this morning.

Emergency services said it was a miracle nobody was injured.

An emergency situation remains in place, with a 1km exclusion zone around the scene.

Northbound lanes of the motorway have reopened but the southbound lanes remain closed as fire crews work to clear chemicals from the site after the fire was extinguished. Southbound traffic was backed up to near Springwood.

For those hoping to avoid the M1 chaos by using the Logan Motorway, it was this afternoon confirmed tolls would be waived from the M1 at the Loganlea toll point to the Gateway merge at Kuraby toll point until 6pm.

Acting Main Roads and Road Safety Minister Steven Miles thanked motorists for their patience but said delays would remain "for some time".

"While the northbound lanes of the M1 have reopened this morning, police advise traffic will be disrupted for much of the afternoon and the southbound lanes will remain closed for some time." Mr Miles said.

"Anyone thinking of travelling between the Gold Coast, Brisbane and Logan this afternoon is advised to take these travel disruptions into account and plan accordingly."

"Toll tags will still beep when travelling underneath a tolling point, however tolls will not be charged between 10.45am today and 6pm tonight."

An exclusion zone, which encompasses a 1km radius around the crash site, was established amid fears the truck was carrying a "volatile substance", which police confirmed is hydrochloric acid.

The emergency declaration remains in place and police have urged motorists to be mindful of delays "into the afternoon".

Clinical Support Officer Ross Hodges praised the truck driver for his actions.

"The truck driver luckily managed to pull over to the side of the road and get out very quickly," he said.

"He recognised the situation was quite serious early on. He managed to have the foresight to pull over onto the side of the M1 and managed to call emergency services very quickly and also flag down other passing motorists to get them to come to a standstill.

"The fire appeared to actually be coming from his cab somewhere."

Queensland Fire and Emergency Service Inspector Jed Crosby told the ABC: "I believe it is a miracle he has escaped without any injuries."

Mr Hodges said emergency services were called to the scene of the incident just after 8.30am.

"When we arrived on scene we found the truck to be fully ablaze and firefighters were quick to put the blaze out," he said.

In a media statement, the company that owns the truck, Coogee Chemicals, said it was assisting emergency services with the clean-up.

"Coogee Chemicals confirms that one of the trucks caught fire on the M1 at Loganholme this morning. The truck contained 15,000 litres of hydrochloric acid," it said.

"Coogee Chemicals' incident response team is site and working with emergency services to resolve the issue.

"The company is relieved that no-one has been injured in the incident but is concerned about disruption or distress to local residents, businesses and passers-by."

Police earlier told motorists to be patient as the clean-up would take some time.

"A recovery vehicle is enroute and once the truck is empty, it will be loaded on and taken away under police escort," police said this morning.

"Traffic will be disrupted for much of the afternoon and the southbound lanes will remain closed for some time."

A tow truck was at the scene by 1pm but it is understood the remaining hydrochloric acid was yet be decanted from the vehicle.

Scientific and environmental officers were also called in to assess the situation.

The cause of the fire is yet to be determined.

No other vehicles are believed to have been involved in the incident.

EARLIER: AN EMERGENT situation has been declared after a truck carrying a "volatile substance" reportedly burst into flames on the M1 at Loganholme.

Both directions of the motorway remain blocked as fire crews work to extinguish the blaze, which is understood to be under control.

An exclusion zone, which encompasses a 1km radius around the crash site, has been established amid fears the truck was carrying a "volatile substance", which police have since confirmed is hydrochloric acid.

Police have urged motorists to be mindful of delays and have encouraged nearby residents to stay indoors.

Scientific officers have also been called to the scene.

Emergency services were initially called to the incident about 8.40am when the truck caught fire.